"Israel is “troubled” by the entry of Egyptian tanks into the northern Sinai Peninsula without coordination with Israel, a violation of the terms of the 33-year-old peace treaty between the two countries, and has asked Egypt to withdraw them, an Israeli government official said Tuesday.

The Israeli request was conveyed within the last few days, the official said, adding that it was likely that the Obama administration had made a similar approach to Cairo.

The Israeli official was speaking on the condition of anonymity because of the fragility of Israel’s relations with Egypt, already strained by the recent upheavals there. The overthrow of President Hosni Mubarak last year stripped Israel of a trusted regional ally."